Onyx Ring Discussion

Yeah I know it's not for the ring, but it's still something I want to do. Where can I find those mobs though?

You have to hunt mobs up to 20 levels below yours, to get Elite Mobs to spawn, about every 100 kills IME.
After about a dozen Elite Mobs, an Elite Boss might spawn instead.
There are four types of Elite Bosses, I think. Two of them don't count for this quest.

So yeah, quite a few hours of grinding.

However, when such a boss spawns, a notice appears in all maps on the same channel of the same general area ("continent"?). So you can just stay in such a map in a popular botting area and keep CC'ing until you see that notice, and then hurry to the map and hope to get there before the boss is dead. Some people use this method to "farm" Elite Boss drops (such as protection scrolls). It is, of course, forbidden, as it is "benefitting from hacking activity". But now Nexon wants to teach it to everyone who hasn't tried it yet. Excellent event quest. Very educational.